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Groups > comp.os.linux.misc > #92873 > unrolled thread
| Started by | Lars Poulsen <lars@beagle-ears.com> |
|---|---|
| First post | 2026-10-04 14:08 -0700 |
| Last post | 2026-10-05 09:19 +0100 |
| Articles | 20 on this page of 34 — 13 participants |
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Linux needs less fragmentation Lars Poulsen <lars@beagle-ears.com> - 2026-10-04 14:08 -0700
Re: Linux needs less fragmentation Michael Logies <logies@t-online.de> - 2026-10-04 23:33 +0200
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 09:20 +0100
Re: Linux needs less fragmentation Leroy H <lh@somewhere.net> - 2026-10-04 21:44 +0000
Re: Linux needs less fragmentation rbowman <bowman@montana.com> - 2026-10-05 01:53 +0000
Re: Linux needs less fragmentation c186282 <c186282@nnada.net> - 2026-10-05 03:14 -0400
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 09:28 +0100
Re: Linux needs less fragmentation "Carlos E. R." <robin_listas@es.invalid> - 2026-10-05 19:20 +0200
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 19:43 +0100
Re: Linux needs less fragmentation Andy Burns <usenet@andyburns.uk> - 2026-10-08 15:25 +0100
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-08 15:29 +0100
Re: Linux offers choice, BSD offers fragmentation Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-10-08 20:59 +0000
Re: Linux needs less fragmentation c186282 <c186282@nnada.net> - 2026-10-09 02:42 -0400
Re: Linux needs less fragmentation "Carlos E. R." <robin_listas@es.invalid> - 2026-10-09 20:47 +0200
Re: Linux offers choice, BSD offers fragmentation Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-10-09 21:20 +0000
Re: Linux offers choice, BSD offers fragmentation "Carlos E. R." <robin_listas@es.invalid> - 2026-10-09 23:27 +0200
Re: Linux offers choice, BSD offers fragmentation c186282 <c186282@nnada.net> - 2026-10-10 04:01 -0400
Re: Linux offers choice, BSD offers fragmentation c186282 <c186282@nnada.net> - 2026-10-11 04:31 -0400
Re: Linux needs less fragmentation Rich <rich@example.invalid> - 2026-10-05 18:57 +0000
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 20:08 +0100
Re: Linux needs less fragmentation Rich <rich@example.invalid> - 2026-10-05 20:18 +0000
Re: Linux needs less fragmentation Richard Kettlewell <invalid@invalid.invalid> - 2026-10-06 08:34 +0100
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-06 11:17 +0100
Re: Linux needs less fragmentation c186282 <c186282@nnada.net> - 2026-10-06 23:59 -0400
Re: Linux needs less fragmentation rbowman <bowman@montana.com> - 2026-10-06 14:39 +0000
Re: Linux needs less fragmentation Chris Ahlstrom <OFeem1987@teleworm.us> - 2026-10-06 13:50 -0400
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 09:25 +0100
Re: Linux needs less fragmentation rbowman <bowman@montana.com> - 2026-10-05 19:36 +0000
Re: Linux needs less fragmentation "Carlos E. R." <robin_listas@es.invalid> - 2026-10-05 21:49 +0200
Re: Linux needs less fragmentation rbowman <bowman@montana.com> - 2026-10-06 02:35 +0000
Re: Linux needs less fragmentation Philippe <p.naudin+nntp@free.fr> - 2026-10-06 08:13 +0200
Re: Linux needs less fragmentation "Carlos E. R." <robin_listas@es.invalid> - 2026-10-06 11:12 +0200
Re: Linux needs less fragmentation rbowman <bowman@montana.com> - 2026-10-06 14:48 +0000
Re: Linux needs less fragmentation The Natural Philosopher <tnp@invalid.invalid> - 2026-10-05 09:19 +0100
Page 1 of 2 [1] 2 Next page →
| From | Lars Poulsen <lars@beagle-ears.com> |
|---|---|
| Date | 2026-10-04 14:08 -0700 |
| Subject | Linux needs less fragmentation |
| Message-ID | <119uf8l$9egg$1@dont-email.me> |
On 10/4/2026 02:47, Daniel70 wrote: > On 3/10/2026 10:01 pm, CrudeSausage wrote: >> On 2026-10-02 8:23 p.m., Paul wrote: >>> On Fri, 10/2/2026 1:17 PM, CrudeSausage wrote: >>>> On 2026-10-02 1:03 p.m., CrudeSausage wrote: > [...] > Yeap, for sure .... but the problem (as I see it) is that Linux is > soooo flexible that everyone modifies the BASE LINUX OS to suit THEIR > needs (Me, Mageia!! eventually) whereas MicroSoft releases Windows "AND > YOU *WILL* USE IT THE WAY *WE* WANT"!! > > If only Linux Devs could get together!! ;-P Pipe Dreams!! > > But thank you Devs!! A lot of the noise is "Ubuntu based distributions" and "Fedora based distributions". In my opinion, those should not be distributions, they should be packages to load on top of those mainstream distributions. In the cases that I am aware of, they are basically tweaks to the GUI to suit a particular taste. Reducing the noise would help newbies understand the field much better. -- Lars Poulsen - an old geek in Santa Barbara, California
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| From | Michael Logies <logies@t-online.de> |
|---|---|
| Date | 2026-10-04 23:33 +0200 |
| Message-ID | <clg5cl5vqgfu9l0s13uih6i5f9rp5buqh0@4ax.com> |
| In reply to | #92873 |
On Sun, 4 Oct 2026 14:08:35 -0700, Lars Poulsen <lars@beagle-ears.com> wrote: >Reducing the noise would help newbies understand the field much better. Linux Mint has consistently ranked at or near the top on DistroWatch for years. I run the flagship Cinnamon edition, which I consider the ideal choice for Linux newcomers. Thanks to its Ubuntu foundation and extensive documentation, an integrated AI agent like Qwen Code can easily manage the system. I have coupled it with a local memory system, enabling the agent to retain context and recall past operations: https://www.logies.de/memory-mcp-for-ai-agents.html
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2026-10-05 09:20 +0100 |
| Message-ID | <119vmkk$mtek$11@dont-email.me> |
| In reply to | #92874 |
On 04/10/2026 22:33, Michael Logies wrote: > On Sun, 4 Oct 2026 14:08:35 -0700, Lars Poulsen <lars@beagle-ears.com> > wrote: > >> Reducing the noise would help newbies understand the field much better. > > Linux Mint has consistently ranked at or near the top on DistroWatch > for years. I run the flagship Cinnamon edition, which I consider the > ideal choice for Linux newcomers. Thanks to its Ubuntu foundation and > extensive documentation, an integrated AI agent like Qwen Code can > easily manage the system. I have coupled it with a local memory > system, enabling the agent to retain context and recall past > operations: https://www.logies.de/memory-mcp-for-ai-agents.html Amen. I run MATE but that's because I left windows around XP time and I never got used to eye candy -- How fortunate for governments that the people they administer don't think. Adolf Hitler
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| From | Leroy H <lh@somewhere.net> |
|---|---|
| Date | 2026-10-04 21:44 +0000 |
| Message-ID | <18db71b0c1a24794$5518$2522880$802601b3@news.usenetexpress.com> |
| In reply to | #92873 |
On Sun, 4 Oct 2026 14:08:35 -0700, Lars Poulsen wrote: > > A lot of the noise is "Ubuntu based distributions" and "Fedora based > distributions". In my opinion, those should not be distributions, they > should be packages to load on top of those mainstream distributions. > In the cases that I am aware of, they are basically tweaks to the GUI to > suit a particular taste. > What is Linux? Linux is an OS which means that it provides (configurable) access to hardware from "user space." There is nothing more. The question then becomes "what is user space?" and this is where the distributions come in. A distribution provides "user space" for all those who cannot provide it for themselves. There can be many, many choices for user space. Consequently, there should be many, many different choices for a distribution. But there are not. Most distros align with RedHat, Debian, or Arch. Your assertion about "noise" is false. The noise is only an illusion. Beneath it all is total sameness. GNU/Linux is being highly circumscribed by both the popular distros and the acquiescence of its users.
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| From | rbowman <bowman@montana.com> |
|---|---|
| Date | 2026-10-05 01:53 +0000 |
| Message-ID | <nige8jFoo9pU34@mid.individual.net> |
| In reply to | #92873 |
On Sun, 4 Oct 2026 14:08:35 -0700, Lars Poulsen wrote: > A lot of the noise is "Ubuntu based distributions" and "Fedora based > distributions". In my opinion, those should not be distributions, they > should be packages to load on top of those mainstream distributions. > In the cases that I am aware of, they are basically tweaks to the GUI to > suit a particular taste. Ubuntu has a few GNOME tweaks that make it more usable than vanilla GNOME. KDE on Fedora, Arch, and SUSE are all very similar with little customization. MX does a nice job with Xfce, better than Debian or Devuan. Ubuntu has Lubuntu, Xubuntu, Kubuntu. Mint offers Cinnamon, MATE, and Xfce with separate isos for each. Fedora has 'spins' with GNOME and KDE now as mainstream. SUSE includes GNOME, KDE, and Xfce in the offline installer. Devuan has those and a couple of more. What you're overlooking is some of the other differences. Rolling, semi- rolling, or slow releaes. Snpa, flatpak, or nothing by default? Systemd, SysVinit, runit? X11 or Wayland?
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| From | c186282 <c186282@nnada.net> |
|---|---|
| Date | 2026-10-05 03:14 -0400 |
| Message-ID | <cpWdneUfD_vF0173nZ2dnZfqn_udnZ2d@giganews.com> |
| In reply to | #92884 |
On 10/4/26 21:53, rbowman wrote: > On Sun, 4 Oct 2026 14:08:35 -0700, Lars Poulsen wrote: > >> A lot of the noise is "Ubuntu based distributions" and "Fedora based >> distributions". In my opinion, those should not be distributions, they >> should be packages to load on top of those mainstream distributions. >> In the cases that I am aware of, they are basically tweaks to the GUI to >> suit a particular taste. > > Ubuntu has a few GNOME tweaks that make it more usable than vanilla GNOME. > KDE on Fedora, Arch, and SUSE are all very similar with little > customization. MX does a nice job with Xfce, better than Debian or Devuan. > > Ubuntu has Lubuntu, Xubuntu, Kubuntu. Mint offers Cinnamon, MATE, and Xfce > with separate isos for each. Fedora has 'spins' with GNOME and KDE now as > mainstream. SUSE includes GNOME, KDE, and Xfce in the offline installer. > Devuan has those and a couple of more. > > What you're overlooking is some of the other differences. Rolling, semi- > rolling, or slow releaes. Snpa, flatpak, or nothing by default? Systemd, > SysVinit, runit? X11 or Wayland? MANY choices these days ... a lot better than Winders. Linux is "fairly" resistant to disk fragmentation, better than Win for the most part. Some of the utils can kind-of deal with it. However if things get really bad, like on a server drive, in the end you have to copy over to a new drive. This is not guarenteed to get the boot/efi sectors alas. 'dd' is TOO literal, won't fix yer frag. Some say that frag is NOT important anymore due to e-disks. Sort-of true, sort-of not. In the end you will get more and more kinda unusable sectors. I still have a few big magnetics ... frag IS important.
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2026-10-05 09:28 +0100 |
| Message-ID | <119vn39$mtek$13@dont-email.me> |
| In reply to | #92904 |
On 05/10/2026 08:14, c186282 wrote: > MANY choices these days ... a lot better than Winders. > > Linux is "fairly" resistant to disk fragmentation, > better than Win for the most part. Some of the utils > can kind-of deal with it. However if things get > really bad, like on a server drive, in the end you > have to copy over to a new drive. This is not > guarenteed to get the boot/efi sectors alas. 'dd' > is TOO literal, won't fix yer frag. > Never had to in years. SSDs simply dont care, since a sector seek is no more expensive than 'next sector' > Some say that frag is NOT important anymore due to > e-disks. Sort-of true, sort-of not. In the end you > will get more and more kinda unusable sectors. > More ignorant bollocks > I still have a few big magnetics ... frag IS important. It would be if you were running multiple parallel tasks, but then you would be using RAID anyway and enough RAM to cache a whole Tuesday -- "When one man dies it's a tragedy. When thousands die it's statistics." Josef Stalin
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| From | "Carlos E. R." <robin_listas@es.invalid> |
|---|---|
| Date | 2026-10-05 19:20 +0200 |
| Message-ID | <nii4iaFhu1lU1@mid.individual.net> |
| In reply to | #92919 |
On 2026-10-05 10:28, The Natural Philosopher wrote:
> On 05/10/2026 08:14, c186282 wrote:
>> MANY choices these days ... a lot better than Winders.
>>
>> Linux is "fairly" resistant to disk fragmentation,
>> better than Win for the most part. Some of the utils
>> can kind-of deal with it. However if things get
>> really bad, like on a server drive, in the end you
>> have to copy over to a new drive. This is not
>> guarenteed to get the boot/efi sectors alas. 'dd'
>> is TOO literal, won't fix yer frag.
>>
> Never had to in years.
> SSDs simply dont care, since a sector seek is no more expensive than
> 'next sector'
True, but next sector might be in the cache. Might, dunno how an SSD
does internal caching. There is still system caching.
--
Cheers,
Carlos E.R.
ES🇪🇸, EU🇪🇺.
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2026-10-05 19:43 +0100 |
| Message-ID | <11a0r44$179lq$3@dont-email.me> |
| In reply to | #92951 |
On 05/10/2026 18:20, Carlos E. R. wrote: > On 2026-10-05 10:28, The Natural Philosopher wrote: >> On 05/10/2026 08:14, c186282 wrote: >>> MANY choices these days ... a lot better than Winders. >>> >>> Linux is "fairly" resistant to disk fragmentation, >>> better than Win for the most part. Some of the utils >>> can kind-of deal with it. However if things get >>> really bad, like on a server drive, in the end you >>> have to copy over to a new drive. This is not >>> guarenteed to get the boot/efi sectors alas. 'dd' >>> is TOO literal, won't fix yer frag. >>> >> Never had to in years. >> SSDs simply dont care, since a sector seek is no more expensive than >> 'next sector' > > True, but next sector might be in the cache. Might, dunno how an SSD > does internal caching. There is still system caching. > > SSD caches a block when reading. And IIRC a larger page when writing Erase blocks are even larger IN all cases response shows no 'seek' delays. Writes are fully cached and written behind in SSD time. The application has no control, over that. Ultimately Linux cacheing is probably completely irrelevant. -- The difference bweteen a psychopath and a saint is that the psychpoath takes what he can and gives only what he must, but the saint gives everything he can and takes only what he needs.
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| From | Andy Burns <usenet@andyburns.uk> |
|---|---|
| Date | 2026-10-08 15:25 +0100 |
| Message-ID | <nipnemFmrjqU1@mid.individual.net> |
| In reply to | #92955 |
The Natural Philosopher wrote: > SD caches a block when reading. > > And IIRC a larger page when writing > > Erase blocks are even larger > > IN all cases response shows no 'seek' delays. > > Writes are fully cached and written behind in SSD time. The application > has no control, over that. > > Ultimately Linux cacheing is probably completely irrelevant. By themselves, SSDs have no concept of which blocks are in-use by the host's filesystem, use of TRIM commands allow O/S to tell the internal controller to mark unused blocks for coalescing into larger blocks for erasing. So no they don't care in terms of seek times, or needing traditional defragging, but they do care in terms of avoiding extra writes during garbage collection (blocks can't be overwritten, only re-written within those larger erased blocks).
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2026-10-08 15:29 +0100 |
| Message-ID | <11a89d2$3t265$1@dont-email.me> |
| In reply to | #93181 |
On 08/10/2026 15:25, Andy Burns wrote: > The Natural Philosopher wrote: > >> SD caches a block when reading. >> >> And IIRC a larger page when writing >> >> Erase blocks are even larger >> >> IN all cases response shows no 'seek' delays. >> >> Writes are fully cached and written behind in SSD time. The >> application has no control, over that. >> >> Ultimately Linux cacheing is probably completely irrelevant. > By themselves, SSDs have no concept of which blocks are in-use by the > host's filesystem, use of TRIM commands allow O/S to tell the internal > controller to mark unused blocks for coalescing into larger blocks for > erasing. > > So no they don't care in terms of seek times, or needing traditional > defragging, but they do care in terms of avoiding extra writes during > garbage collection (blocks can't be overwritten, only re-written within > those larger erased blocks). > Yes. in terms of wear levelling. No, in terms of access speeds, as you said More important is to try not to fill them up. So the internal firmware has the space to shuffle and consolidate 'sectors; -- “Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong remedies.” ― Groucho Marx
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| From | Lawrence D’Oliveiro <ldo@nz.invalid> |
|---|---|
| Date | 2026-10-08 20:59 +0000 |
| Subject | Re: Linux offers choice, BSD offers fragmentation |
| Message-ID | <11a907g$6ume$2@dont-email.me> |
| In reply to | #93181 |
On Thu, 8 Oct 2026 15:25:21 +0100, Andy Burns wrote: > By themselves, SSDs have no concept of which blocks are in-use by > the host's filesystem, use of TRIM commands allow O/S to tell the > internal controller to mark unused blocks for coalescing into larger > blocks for erasing. SSDs come with an amazing amount of firmware to make them behave as though they were conventional disks to the OS. Think of the overhead on performance this imposes, as well as the potential for weird bugs. The Linux kernel includes a few filesystems that are purpose-built to operate on raw flash devices, by including wear-levelling directly into their allocation algorithms. I think these are deployed in embedded applications. But imagine if you had the option to use them and bypass the pretend-to-be-a-disk firmware on consumer devices.
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| From | c186282 <c186282@nnada.net> |
|---|---|
| Date | 2026-10-09 02:42 -0400 |
| Message-ID | <ZrOdnbPRXIVOEVX3nZ2dnZfqnPGdnZ2d@giganews.com> |
| In reply to | #93181 |
On 10/8/26 10:25, Andy Burns wrote: > The Natural Philosopher wrote: > >> SD caches a block when reading. >> >> And IIRC a larger page when writing >> >> Erase blocks are even larger >> >> IN all cases response shows no 'seek' delays. >> >> Writes are fully cached and written behind in SSD time. The >> application has no control, over that. >> >> Ultimately Linux cacheing is probably completely irrelevant. > By themselves, SSDs have no concept of which blocks are in-use by the > host's filesystem, use of TRIM commands allow O/S to tell the internal > controller to mark unused blocks for coalescing into larger blocks for > erasing. > > So no they don't care in terms of seek times, or needing traditional > defragging, but they do care in terms of avoiding extra writes during > garbage collection (blocks can't be overwritten, only re-written within > those larger erased blocks). SSDs do get rid of a lot of the physical issues with storage. Mag disks have more to cope with more speed/capacity decay issues. As for 'more writes' ... even the SSDs are so relatively slow that it barely matters. The CPU is doing a lot of waiting, time to send 100, or 1000, blocks anywhere IF the device could keep up.
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| From | "Carlos E. R." <robin_listas@es.invalid> |
|---|---|
| Date | 2026-10-09 20:47 +0200 |
| Message-ID | <nisr6hF6jjnU2@mid.individual.net> |
| In reply to | #93181 |
On 2026-10-08 16:25, Andy Burns wrote:
> The Natural Philosopher wrote:
>
>> SD caches a block when reading.
>>
>> And IIRC a larger page when writing
>>
>> Erase blocks are even larger
>>
>> IN all cases response shows no 'seek' delays.
>>
>> Writes are fully cached and written behind in SSD time. The
>> application has no control, over that.
>>
>> Ultimately Linux cacheing is probably completely irrelevant.
> By themselves, SSDs have no concept of which blocks are in-use by the
> host's filesystem, use of TRIM commands allow O/S to tell the internal
> controller to mark unused blocks for coalescing into larger blocks for
> erasing.
>
> So no they don't care in terms of seek times, or needing traditional
> defragging, but they do care in terms of avoiding extra writes during
> garbage collection (blocks can't be overwritten, only re-written within
> those larger erased blocks).
>
I asked chatgpt (as a glorified documentation search engine):
Q: Have SSD disks an internal RAM cache, and what is it used for? I'm interested in normal read operations.
A: Yes. Many SSDs have internal RAM, but it is important to distinguish between RAM used for managing the SSD and RAM used to cache data. For normal read operations, the distinction matters quite a bit.
1. What memory does an SSD have?
1.1. DRAM cache
Some SSDs have a dedicated DRAM chip, typically hundreds of megabytes to several gigabytes in larger drives. It is volatile memory, just like your computer's RAM.
It is primarily used to store the SSD's internal mapping tables, which translate logical block addresses into physical NAND flash locations.
1.2. NAND flash memory
This is the actual nonvolatile storage where your files and data reside. Some SSDs also use portions of their NAND as a cache for writes, but that is a different function from DRAM.
1.3. Controller SRAM
The SSD controller itself typically has a small amount of fast SRAM. It holds temporary data, commands, and metadata while the controller processes requests. This is much smaller than a typical DRAM cache.
Not every SSD has dedicated DRAM. Many budget SSDs are DRAM-less and rely on the controller's internal memory and, in some NVMe designs, the computer's RAM through a feature called Host Memory Buffer (HMB).
2. What happens during a normal read?
Suppose your operating system requests 4 KB from a particular logical address on the SSD.
Operating system / application
Requests a logical block
↓
SSD controller
Looks up the logical-to-physical address mapping
↓
NAND flash
Reads the requested data from flash cells
↑
Data returned to the computer
The DRAM cache is useful mainly in the middle step. It can hold the mapping table so that the controller can quickly find where the requested data lives.
Without DRAM, the controller may need to retrieve mapping information from NAND itself, which can add latency. The exact impact depends on the SSD's design and workload.
3. Does the SSD cache the actual data being read?
It can, but this is not generally the main purpose of an SSD's DRAM.
There are three important cases:
Situation What happens
----------- ---------------
First read of a block The SSD normally fetches the data from NAND flash.
Repeated read of the same block It may be served from a controller buffer if the SSD has retained that data, but this is not guaranteed.
Repeated read of a file by
an application The operating system may serve the data from its own RAM cache, without accessing the SSD at all.
The third case is particularly important. Your computer's operating system typically uses otherwise available RAM to cache recently accessed file data. That cache can be much larger than the SSD's internal RAM.
Also, an SSD may perform internal read-ahead or buffer data temporarily, but its controller does not necessarily retain previously read user data for long-term caching.
4. How much does internal RAM improve read performance?
It depends on the workload.
* Random reads: DRAM can help by making address translation faster, especially when the mapping information would otherwise require extra flash accesses.
* Sequential reads: The SSD can usually read efficiently from NAND in either case. DRAM may help with mapping and request management, but it is not necessarily the main performance bottleneck.
* Repeated reads: The operating system's RAM cache often has a much larger effect than the SSD's internal DRAM.
* Large working sets with random access: A DRAM-equipped SSD can have an advantage, particularly when its mapping tables are large and cannot be held entirely in the controller's small internal memory.
A DRAM-less SSD can still deliver excellent read performance. Modern controllers and HMB can reduce the performance gap substantially for some workloads.
The key takeaway
If you're interested specifically in normal reads, an SSD's internal DRAM is primarily an address-translation cache, not a general-purpose cache of recently read file contents. The NAND flash holds the actual data, while the computer's own RAM is usually the more significant cache for repeated file reads.
One final distinction: a write cache can improve write speed by temporarily accepting data before it is fully committed to NAND. That is a separate issue from the read behavior discussed here.
--
Cheers,
Carlos E.R.
ES🇪🇸, EU🇪🇺.
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| From | Lawrence D’Oliveiro <ldo@nz.invalid> |
|---|---|
| Date | 2026-10-09 21:20 +0000 |
| Subject | Re: Linux offers choice, BSD offers fragmentation |
| Message-ID | <11ablr9$15ru5$3@dont-email.me> |
| In reply to | #93250 |
On Fri, 9 Oct 2026 20:47:45 +0200, Carlos E. R. spouted more AI slop: > I asked chatgpt (as a glorified documentation search engine): A search engine gives references. > Some SSDs have a dedicated DRAM chip, typically hundreds of > megabytes to several gigabytes in larger drives. It is volatile > memory, just like your computer's RAM. > > It is primarily used to store the SSD's internal mapping tables, > which translate logical block addresses into physical NAND flash > locations. This is what an OS filesystem cache does, too. So now you’re going through *two* layers between the application and its data: the OS filesystem implementation itself, plus an additional filesystem-like layer within the drive. All that is extra overhead. > One final distinction: a write cache can improve write speed by > temporarily accepting data before it is fully committed to NAND. > That is a separate issue from the read behavior discussed here. Also one that doesn’t actually work, unless your OS filesystem cache is useless.
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| From | "Carlos E. R." <robin_listas@es.invalid> |
|---|---|
| Date | 2026-10-09 23:27 +0200 |
| Subject | Re: Linux offers choice, BSD offers fragmentation |
| Message-ID | <nit4i7F6jjnU10@mid.individual.net> |
| In reply to | #93263 |
On 2026-10-09 23:20, Lawrence D’Oliveiro wrote:
> On Fri, 9 Oct 2026 20:47:45 +0200, Carlos E. R. spouted more AI slop:
>
>> I asked chatgpt (as a glorified documentation search engine):
>
> A search engine gives references.
So does the AI, but you need to do another operation to collect them.
>
>> Some SSDs have a dedicated DRAM chip, typically hundreds of
>> megabytes to several gigabytes in larger drives. It is volatile
>> memory, just like your computer's RAM.
>>
>> It is primarily used to store the SSD's internal mapping tables,
>> which translate logical block addresses into physical NAND flash
>> locations.
>
> This is what an OS filesystem cache does, too. So now you’re going
> through *two* layers between the application and its data: the OS
> filesystem implementation itself, plus an additional filesystem-like
> layer within the drive. All that is extra overhead.
>
>> One final distinction: a write cache can improve write speed by
>> temporarily accepting data before it is fully committed to NAND.
>> That is a separate issue from the read behavior discussed here.
>
> Also one that doesn’t actually work, unless your OS filesystem cache
> is useless.
--
Cheers,
Carlos E.R.
ES🇪🇸, EU🇪🇺.
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| From | c186282 <c186282@nnada.net> |
|---|---|
| Date | 2026-10-10 04:01 -0400 |
| Subject | Re: Linux offers choice, BSD offers fragmentation |
| Message-ID | <ITKdnZyEHuB5bVT3nZ2dnZfqnPadnZ2d@giganews.com> |
| In reply to | #93263 |
On 10/9/26 17:20, Lawrence D’Oliveiro wrote: > On Fri, 9 Oct 2026 20:47:45 +0200, Carlos E. R. spouted more AI slop: > >> I asked chatgpt (as a glorified documentation search engine): > > A search engine gives references. > >> Some SSDs have a dedicated DRAM chip, typically hundreds of >> megabytes to several gigabytes in larger drives. It is volatile >> memory, just like your computer's RAM. >> >> It is primarily used to store the SSD's internal mapping tables, >> which translate logical block addresses into physical NAND flash >> locations. > > This is what an OS filesystem cache does, too. So now you’re going > through *two* layers between the application and its data: the OS > filesystem implementation itself, plus an additional filesystem-like > layer within the drive. All that is extra overhead. This is why even SSDs don't really live up to their full potential. Every OS just still kind of assumes magnetic drives. And even SSDs/M.2s, compared to DRAM, SLOW ! >> One final distinction: a write cache can improve write speed by >> temporarily accepting data before it is fully committed to NAND. >> That is a separate issue from the read behavior discussed here. > > Also one that doesn’t actually work, unless your OS filesystem cache > is useless. It's all "best kludge". The main idea is to make the system work with 'everything'. Performance is kinda secondary.
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| From | c186282 <c186282@nnada.net> |
|---|---|
| Date | 2026-10-11 04:31 -0400 |
| Subject | Re: Linux offers choice, BSD offers fragmentation |
| Message-ID | <KNmdnTGsC7He1Fb3nZ2dnZfqn_GdnZ2d@giganews.com> |
| In reply to | #93263 |
On 10/9/26 17:20, Lawrence D’Oliveiro wrote: > On Fri, 9 Oct 2026 20:47:45 +0200, Carlos E. R. spouted more AI slop: > >> I asked chatgpt (as a glorified documentation search engine): > > A search engine gives references. > >> Some SSDs have a dedicated DRAM chip, typically hundreds of >> megabytes to several gigabytes in larger drives. It is volatile >> memory, just like your computer's RAM. >> >> It is primarily used to store the SSD's internal mapping tables, >> which translate logical block addresses into physical NAND flash >> locations. On the BSDs ... they ARE "Fit For Purpose" and very secure. But NOT quite as 'versatile' as the latest Linux distros. MOSTLY they are meant for outward-facing SERVERS ... and do their job very well. However, if you are willing to step back just a few years, they are perfectly good personal operating systems. Nicest, for now, "GhostBSD". Not THAT much different from vanilla Debian. The BSDs are an "out" ... if/when Linux gets just TOO stupid you CAN go to the BSDs and not suffer TOO much. People with 'exotic' needs, MAY not be your cup-o-tea however. "Basic Users" though ... I've kept in touch with the BSDs since forever. NOT my first choice, but a FAIR alt choice Just In Case. Do have a little box with Ghost set up even now. If the next-gen Linux distros go just TOO stupid ....... And there's always "Plan-9" :-) Don't forget Solaris/OpenIndiana either. Look, 'popular' pressures will always push the Linux distros out into the blue. This will NOT always be a good thing, not at all. BEST to cultivate some 'retro' stuff. I bought a number of mini-boxes a couple of years ago when they were cheap. This is my reserve. IF needed, BSD/Solaris/Whatever.
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| From | Rich <rich@example.invalid> |
|---|---|
| Date | 2026-10-05 18:57 +0000 |
| Message-ID | <11a0ruk$17kui$2@dont-email.me> |
| In reply to | #92919 |
The Natural Philosopher <tnp@invalid.invalid> wrote: > On 05/10/2026 08:14, c186282 wrote: >> MANY choices these days ... a lot better than Winders. >> >> Linux is "fairly" resistant to disk fragmentation, better than Win >> for the most part. Some of the utils can kind-of deal with it. >> However if things get really bad, like on a server drive, in the >> end you have to copy over to a new drive. This is not guarenteed >> to get the boot/efi sectors alas. 'dd' is TOO literal, won't fix >> yer frag. >> > Never had to in years. > SSDs simply dont care, since a sector seek is no more expensive than > 'next sector' Exactly. >> Some say that frag is NOT important anymore due to e-disks. >> Sort-of true, sort-of not. In the end you will get more and more >> kinda unusable sectors. >> > More ignorant bollocks Our human-AI hallucinating yet another incorrect answer to a question no one asked. He's hallucinating worn out SSD "sectors" and the SSD remapping system as if they have something to do with fragmented files.
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| From | The Natural Philosopher <tnp@invalid.invalid> |
|---|---|
| Date | 2026-10-05 20:08 +0100 |
| Message-ID | <11a0sk2$179lq$6@dont-email.me> |
| In reply to | #92956 |
On 05/10/2026 19:57, Rich wrote: > The Natural Philosopher <tnp@invalid.invalid> wrote: >> On 05/10/2026 08:14, c186282 wrote: >>> MANY choices these days ... a lot better than Winders. >>> >>> Linux is "fairly" resistant to disk fragmentation, better than Win >>> for the most part. Some of the utils can kind-of deal with it. >>> However if things get really bad, like on a server drive, in the >>> end you have to copy over to a new drive. This is not guarenteed >>> to get the boot/efi sectors alas. 'dd' is TOO literal, won't fix >>> yer frag. >>> >> Never had to in years. >> SSDs simply dont care, since a sector seek is no more expensive than >> 'next sector' > > Exactly. > >>> Some say that frag is NOT important anymore due to e-disks. >>> Sort-of true, sort-of not. In the end you will get more and more >>> kinda unusable sectors. >>> >> More ignorant bollocks > > Our human-AI hallucinating yet another incorrect answer to a question > no one asked. He's hallucinating worn out SSD "sectors" and the SSD > remapping system as if they have something to do with fragmented files. It is weird that this conversation seems to crop up, as if there were some actually relationship between a sector as seen by the operating system and a physical RAM location on the SSD. There is none. The SSD is running its own operating system with caches and write behinds , wear levelling, block erases and block reallocation. The only think it needs to know from Linux is if a block is no longer required via the fstrim command, which is run under cron on most distros The only thing you can do to extend SSD lifetime is not fill the disk completely. -- “It is hard to imagine a more stupid decision or more dangerous way of making decisions than by putting those decisions in the hands of people who pay no price for being wrong.” Thomas Sowell
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